The present invention relates to a film cartridge comprising a rewinding shaft for rewinding a film and a case having a film exit/entrance and accommodating the film rewound by the shaft therearound in a light-intercepted condition, and a camera in which the cartridge is used.
More particularly, the present invention relates to a film cartridge having a locking mechanism for locking the leading portion of a film in the vicinity of a film exit/entrance and a camera in which the film cartridge is used. Furthermore, the present invention relates to a film cartridge in which the shaft is set in a predetermined position and a camera employing the cartridge. Moreover, the present invention relates to a camera employing a film cartridge having a film feeding-out mechanism and a film rewinding mechanism and more particularly, to a camera employing a film cartridge in which a film winding operation and a film feeding-out operation are performed after the film cartridge is accommodated in a camera body of the camera. The present invention also relates to a film cartridge which is accommodated in a camera body of a camera in which a film rewinding operation and a film feeding-out operation are automatically performed.
In a known 135-type film cartridge, as shown in FIGS. 23 and 24, a predetermined amount of film 8 projects from a film exit/entrance of a film cartridge 2 when the film is not used. When the film cartridge 2 is accommodated in a film cartridge accommodating chamber 10 of a camera body 1, the leading portion 8a of the film 8 which projects from the film cartridge 2 is engaged by an engaging groove 3a formed on a spool 3 of a film driving mechanism provided with the camera body 1.
In the individual cartridges the length of the leading portion 8a of the film 8 projecting out of a film exit/entrance is different for each camera, and in the individual models of the cameras, the distance between the cartridge accommodating chamber 10 and the spool chamber 11 is different for each camera. Therefore, it is required for an operator to adjust the length of the film pulled out of the film exit/entrance of the 135-type film cartridge 2 in order to engage the leading portion of the film with a predetermined portion of a driving mechanism such as a sprocket. Then, it is troublesome to do such an adjusting operation. Moreover, since, the film 8 is flexible and has the curly tendency, to curl it is difficult for specially those who are not accustomed in the camera to insert the leading portion 8a of the film 8 into the slots 3a. On the other hand, there is known other types of camera in which the leading portion 8a of the film 8 is automatically connected with the spool 3 by an automatic engaging mechanism in the camera as long as the leading portion 8a thereof is put on the spool 3 In such a camera, it is also required for the operator to adjust the length of the leading portion 8a of the film 8 to set the leading portion 8a thereof to a predetermined position on the spool 3.
In order to solve these problems, there has been proposed a film cartridge in which it is not required to perform the film length adjusting operation and the operation for connecting the film with the spool and it is required to perform only an operation for accommodating in the camera body. For example, as shown in FIG. 25, a film cartridge 50, the 110-type film cartridge, comprises a film winding chamber 50a having a film winding shaft, a spool chamber 50b having a film take-up spool, and a film exposure supporting unit 50c disposed between these chambers 50a and 50b, as disclosed in Japanese Patent Publication No. 51 -14382. In this 110-type film cartridge 50, the leading portion of the film not used is previously connected with the spool. In order to set the camera in the condition in which the photographing operation can be performed, only the following operations are required: a back lid 61 of a camera body 60 is opened, and then the 110-type film cartridge 50 is accommodated in a cartridge accommodating chamber 60a of the camera body 60 before the back lid 61 is closed.
In the 110-type film cartridge 50, the film exposure supporting unit 50c is disposed between the film winding chamber 50a and the spool chamber 50b, and then the film exposure supporting unit 50c is accommodated behind lens in the camera body 60. Therefore, in order to accommodate the film cartridge in the camera body, an extra space is required to arrange the film exposure supporting unit 50c behind the lens in the camera body, as compared with a space for accommodating the 135-type film cartridge 2, resulting in the occurrence of such a problem that the camera can not be freely designed because of large limitation.
Furthermore, since in the 110-type film cartridge 50, the film winding chamber 50a and the spool chamber 50b are forwardly projected from the film exposure supporting unit 50c at both of the right and left sides of the unit 50c, there is no space enough to arrange various devices to the camera body in a position before the unit 50c. That is, for example, it is difficult to arrange a focal-plane shutter or a mirror for observing an object in a single-lens reflex camera before the unit 50c. Therefore, only some limited models or kinds of the camera can employ the 110-type film cartridge.
Moreover, since the 110-type film cartridge 50 extra requires the spool chamber 50b and the film exposure supporting chamber 50c, the film cartridge 50 is bulkier than the 135-type film cartridge 2, resulting in the occurrence of such a problem that a large chamber for accommodating the film cartridge is required.
On the other hand, according to a conventional 135-type film cartridge as shown in FIGS. 23 and 24, the rotational phase position of a film rewinding shaft around which a film 8 not used is rewound is not uniform. When the cartridge 2 is accommodated in a cartridge accommodating chamber 10 of a camera body 1, the rewinding shaft of the cartridge 2 does not immediately engage with a rewinding fork of the camera body 1 in most cases. When the rewinding fork is rotated after the cartridge is accommodated in the cartridge accommodating chamber 10, the rewinding shaft engages with the rewinding fork. As a result, the rotation of the rewinding fork is transmitted to the rewinding shaft, whereby a rewinding operation is performed.
Therefore, according to the above-described construction, it takes a considerable long period of time to accommodate the film cartridge in the cartridge accommodating chamber due to the displacement between the rotational phase position of the rewinding shaft of the cartridge and that of the rewinding fork of the camera body. Further, when the rewinding fork rotates, a malfunction or a failure occurs due to an unfavorable engagement.